Download The Philosophy of Mind-Wandering

1
The Philosophy of Mind-Wandering
Zachary C. Irving and Evan Thompson
Abstract and Keywords
Our paper serves as an introduction to a budding field: the philosophy of mindwandering. We begin with a philosophical critique of the standard psychological
definitions of mind-wandering as task-unrelated or stimulus-independent. Although
these definitions have helped bring mind-wandering research onto centre stage in
psychology and cognitive neuroscience, they have substantial limitations that
researchers must overcome to move forward. Specifically, the standard definitions do
not account for (i) the dynamics of mind wandering, (ii) task-unrelated thought that
does not qualify as mind-wandering, and (iii) the ways that mind-wandering can be taskrelated. We then survey three philosophical accounts that improve upon the current
psychological definitions. We first present our account of mind-wandering as “unguided
thinking”. Next we review Thomas Metzinger’s view that mind-wandering can be
defined as thought lacking meta-awareness and cognitive agency, as well as Peter
Carruthers’s and Fabian Dorsch’s definitions of mind-wandering as disunified thinking.
We argue that these latter views are inadequate, and we show that our definition of
mind-wandering as unguided thinking is not only conceptually and phenomenologically
precise but also can be operationalized in a principled way for empirical research.
Keywords: mind-wandering, philosophy, guidance, rumination, goal-directed thought,
task-unrelated thought, stimulus-independent thought, daydreaming, agency,
spontaneity
1 Introduction
Before the twenty-first century, research on the wandering mind was “relegated to the
backwaters of mainstream empirical psychology” (Smallwood & Schooler, 2006, p. 956).
Not anymore. Indeed, some researchers have dubbed our time “the era of the
2
wandering mind” (Callard, Smallwood, Golchert, & Margulies, 2013). Nevertheless,
because the cognitive science of mind-wandering is so young, foundational questions
remain unanswered. In particular, there is no consensus about how to define mindwandering (Christoff, 2012; Irving, 2015). Recent philosophical work on mind-wandering
addresses this foundational issue (Carruthers, 2015; Dorsch, 2014; Irving, 2015;
Metzinger, 2013, 2015; Sutton, 2010; Thompson, 2015). In this chapter we provide an
introduction to the philosophy of mind-wandering and we argue that mind-wandering is
best defined as “unguided thinking” (Irving, 2015).
We begin by criticizing the standard definitions of mind-wandering in
psychology, according to which mind-wandering is “task-unrelated thought” or
“stimulus-independent thought” (see Irving, 2015). Using these definitions, scientists
have produced important findings and have brought mind-wandering onto centre stage
in psychology and cognitive neuroscience (Schooler, Smallwood, Christoff, Handy,
Reichle, & Sayette, M. A., 2011; Smallwood & Schooler, 2006, Smallwood & Schooler,
2015). Nevertheless, these definitions have substantial limitations that must be
overcome in order for research to move forward. Specifically, the standard definitions
do not account for (i) the dynamics of mind wandering, (ii) task-unrelated thought that
does not qualify as mind-wandering, and (iii) the ways that mind-wandering can be taskrelated.
We then survey three philosophical accounts that improve upon the current
psychological definitions in various ways. We first present our account of mindwandering as “unguided thinking” (Irving, 2015). Next we review Thomas Metzinger’s
(2013) view that mind-wandering can be defined as thought lacking meta-awareness
and cognitive agency, as well as Peter Carruthers’s (2015) and Fabian Dorsch’s (2014)
definitions of mind-wandering as disunified thinking. We argue that these views are
inadequate, and we show that our definition of mind-wandering as unguided thinking is
not only conceptually and phenomenologically precise but also can be operationalized
in a principled way for empirical research.
3
2 Mind-Wandering as Task-Unrelated Thought or Stimulus-Independent Thought
Experientially, we all know mind-wandering when we see it. On the commute home, a
programmer’s thoughts drift away from the sights and sounds of the subway car. At first
she imagines the chicken she is brining for dinner. She can almost taste the thyme and
rosemary when, suddenly, a line of code pops into her head. She plays with the code for
a while, and then, smiling, remembers a joke she heard today… and so on. Clearly, the
programmer’s mind is wandering. But what exactly makes her train of thought a case of
mind-wandering? What precisely is mind-wandering?
Scientists in the empirical literature typically define mind-wandering as thought
that is “task-unrelated” or “stimulus-independent,” or both. For example, Jonathan
Smallwood and Jonathan Schooler define mind-wandering as “a shift in the contents of
thought away from an ongoing task and/or from events in the external environment to
self-generated thoughts and feelings” (Smallwood & Schooler, 2015, p. 488). This
definition correctly identifies paradigm cases of mind-wandering. For example, the
programmer’s wandering thoughts are unrelated to her ongoing task—commuting
home—and to her external environment—the subway car.
Nevertheless, this definition abstracts away from a central feature of mindwandering, namely, its dynamics (Christoff, 2012; Irving, 2015). Wandering trains of
thought unfold in a distinctive way over time. Experientially, the thoughts seem to drift
freely from one topic (a line of code) to another one (a joke). Irving (2015) notes that
the term “mind-wandering” reflects this dynamics: according to the Oxford English
Dictionary (Online), “to wander” means “to move hither and thither without fixed
course or certain aim.” The above definition of mind-wandering, however, focuses only
on individual mental states and seeks to determine whether their content is related to
one’s task or environment. This focus tells us nothing about how trains of thought
unfold over time. As we now argue, this definition of mind-wandering in static terms is
unsatisfactory in two ways: it cannot differentiate between mind-wandering and other
kinds of task-unrelated and stimulus-independent thought; and it cannot account for
the fact that mind-wandering can be task-related.
4
Varieties of Task-Unrelated Thought
Current definitions of mind-wandering cannot distinguish it from depressive rumination,
which is typically task-unrelated and stimulus-independent, but which has dynamics
that fundamentally differ from that of mind-wandering (Irving, 2015).
Rumination is “a mode of responding to distress that involves repetitively and
passively focusing on symptoms of distress and on the possible causes and
consequences of these symptoms… People who are ruminating remain fixated on the
problems and on their feelings about them” (Nolen-Hoeksema, Wisco, & Lyubomirsky,
2008). Rumination is strongly associated with major depressive disorder, but also is
found in the normal population (Zetsche & Joormann, 2011). For example, a nondepressed teacher might ruminate about how to discipline a problem student.
Rumination is frequently task-unrelated and stimulus independent. For
example, when a teacher ruminates about a problem student during her commute
home, her thoughts are unrelated to her current task (commuting home) and
perceptual environment (the subway train). Current researchers, therefore, classify
rumination as a form of mind-wandering (e.g. Jonathan Smallwood & Schooler, 2006,
2015).
Rumination, however, seems antithetical to mind-wandering. Consider the
ruminating teacher in contrast to the programmer whose mind is wandering. Both
individuals have task-unrelated and stimulus-independent thoughts on the commute
home. But the dynamics of their thoughts could hardly contrast more: whereas the
teacher’s thoughts fixate on her problem student, the programmer’s thoughts drift from
dinner to her computer code to a joke. In general, whereas rumination remains fixed on
a single topic, mind-wandering drifts from one topic to the next. One has not wandered
– “moved hither and thither” – if one has stayed on a single spot.
5
Mind-Wandering and Goal-Directed Thought: A Dilemma
Current definitions of mind-wandering face a dilemma concerning the relationship
between mind-wandering and cognitive tasks. On the one hand, if we say that all
stimulus-independent thinking is mind-wandering, then some mind-wandering will be
task-related, because some stimulus-independent thinking is goal-directed. On the other
hand, if we say that mind-wandering must be task-unrelated thinking, then we run afoul
of empirical evidence that suggests that mind-wandering can be task-related. Let us
explain each alternative and its problems in turn.
Suppose we define mind-wandering as any and all stimulus-independent
thought. Smallwood and Schooler adopt this view, because they define mind-wandering
as “a shift in the contents of thought away from an ongoing task and/or from events in
the external environment” (2015, p. 488 emphasis added). According to the most
restrictive conception in the literature, stimulus-independent mental states are not only
non-perceptual states but also are unrelated to any immediately present perceptual
stimuli (Schooler, Smallwood, Christoff, Handy, Reichle, & Sayette, M. A., 2011). For
example, imagining or thinking about kicking the pigeon in front of you would not count
as a stimulus-independent thought but rather as a stimulus-related thought. Similarly, in
a visual detection experiment, thinking “these pictures are flashing by too quickly,”
would count as a stimulus-related thought, not a stimulus-independent one.
Nevertheless, even this restricted specification of what is required for a thought to be
stimulus-independent—that it be a non-perceptual state unrelated to any immediately
present perceptual stimuli—classifies much of our goal-directed thought as stimulusindependent and hence (counterintuitively) as mind-wandering.
Consider a mathematician solving a proof in her head or a politician rehearsing
a speech under her breath. Both women have thoughts unrelated to their external
environments, so they count as mind-wandering, despite their thinking being goaldirected. The problem is that one’s thoughts cannot wander—“move hither and thither
without fixed course or certain aim”—if they are directed by a goal. Indeed, theorists at
least since Thomas Hobbes (1651) have defined mind-wandering in contrast to goal-
6
directed cognition. In one of the first European philosophical discussions of mindwandering, Hobbes states that thoughts that “wander…seem impertinent to each
other, as in a Dream” (1651, p. 20). In contrast, he wrote that goal-directed thinking is
“more constant; as being regulated by some desire, and designe. For the impression
made by such things as wee desire, or feare, is strong and permanent, or, (if it cease for
a time,) of quick return” (1651, pp. 20–21).
To distinguish mind-wandering from goal-directed thought, we could maintain
that all mind-wandering is task-unrelated thought. According to this conception, neither
the mathematician thinking about her proof nor the politician thinking about her speech
is mind-wandering, because both are thinking about a task.
But now we face the second horn of the dilemma: some mind-wandering is
task-related (Irving, 2015). Consider our vignette of a programmer whose mind is
wandering on her commute home. Her thoughts drift to two personal goals—making
dinner and writing code. Empirical evidence indicates that our minds often wander in
this way to personal goals (Klinger, 1999). Indeed, one study reported that at least
twenty-five percent of a person’s wandering thoughts are about a “specific goal (defined
as an objective or desired result that an individual endeavours to achieve)” (Baird,
Smallwood, & Schooler, 2011, p. 1606). Another study found similar results with an
experimentally induced goal. Participants were told that they would be quizzed on the
names of U.S.A. states after a “concentration task” (Morsella, Ben-Zeev, Lanska, &
Bargh, 2010). When participants had this goal, approximately 70% of their wandering
thoughts were about geography (especially U.S. state names). In contrast, the minds of
participants in control conditions wandered to geography less than 10% of the time. This
finding suggests that goals cause our minds to wander to goal-relevant information.
To see how such findings bear on the current definitions of mind-wandering,
we must consider how “task-unrelated” is defined in the scientific literature. Laboratory
studies define mind-wandering as thought that is unrelated to the experimental task
(e.g. Christoff, Gordon, Smallwood, Smith, & Schooler, 2009). So far, so good: thoughts
7
about personal goals such as making dinner are unrelated to the experimental task, and
so correctly count as mind-wandering.
In studies of “real-world” mind-wandering outside the lab, however, “tasks” are
operationally defined as whatever the person is currently doing. For example,
participants are asked whether “my mind had wandered to something other than what I
was doing” (Kane et al., 2007, p. 616 emphasis added), or “are you thinking about
something other than what you’re currently doing?” (Killingsworth & Gilbert, 2010, p.
932 emphasis added).
Here is the problem. What you are doing often includes working toward the
personal goals to which your mind wanders. For example, if we ask you, “what are you
doing?”, it would be natural for you to answer, “planning dinner” or “preparing for a
test.” Therefore, rather than supposing that mind-wandering is task-unrelated thought,
we could argue that individuals switch tasks when their minds begin wander. According
to this view, when the programmer’s mind wanders to computer code on the commute
home, her task switches to coding from watching for her subway stop. Relative to the
new task of coding, her thoughts about code count as task-related.
We can now bring the dilemma into full view. On the one hand, if we say that
any and all stimulus-independent thought is mind-wandering, then we muddy the
distinction between mind-wandering and goal-directed thinking. On the other hand, if
we try to hold onto this distinction by supposing that mind-wandering must be taskunrelated thinking, then we contradict the empirical evidence that shows that taskrelated mind-wandering is not only possible but frequently actual.
Our diagnosis of the dilemma highlights the dynamics of mind-wandering. The
distinction between mind-wandering versus goal-directed thinking does not concern
whether mental states are task-unrelated or stimulus-independent. Rather, the
distinction concerns how trains of thought unfold over time. When a mathematician
solves a problem in her head, she maintains her attention on this problem for a
prolonged period of time. In contrast, wandering thoughts “move hither and thither,”
drifting between topics unchecked. Because current definitions of mind-wandering
8
abstract away from its dynamics, they cannot distinguish mind-wandering from either
rumination or goal-directed thinking. We now propose a theory that overcomes these
limitations: mind-wandering is unguided thinking (Irving, 2015).
3 Mind-Wandering is Unguided Thinking
We define mind-wandering as unguided thinking. This definition depends on a particular
concept of guidance taken from the philosophy of action. Thought or behavior is said to
be guided when it is monitored and regulated as it unfolds over time (Pacherie, 2008;
Railton, 2006). Harry Frankfurt provides a classic philosophical explanation of guidance:
Behaviour is purposive when its course is subject to adjustments which
compensate for the effects of forces which would otherwise interfere with
the course of the behaviour… This is merely another way of saying that their
course is guided (Frankfurt, 1978, pp. 159–160)
According to this account, “guidance” includes as part of its meaning a
counterfactual aspect. To say that behaviour is guided implies the following: were it to
go off course or deviate from some standard—as a result, for example, of interfering
forces—one would alter it in order to bring it back on course. In other words, as
Frankfurt states, guidance implies adjusting behaviour to compensate for deviations.
Thus the concept of guidance also includes a normative aspect: it implies the monitoring
and correcting of behaviour in relation to some norm or standard. For example, consider
conversational interaction. In a conversation, you are guided to maintain a certain
distance from your partner, for were your partner to stand too close to you, you would
feel discomfited and drawn to step back (Brownstein & Madva, 2012). In other words,
your behaviour is guided in the sense that it compensates for deviations from the
(culturally specific) standards or norms of conversation. It follows that for behaviour to
be guided there must be regulatory processes for bringing “deviant” behaviour back on
track.
9
We use this technical concept of guidance in order to specify what it means for
thought to be guided. We propose that one’s thinking is guided only if one would feel
pulled back to its topic, were one distracted from it. We also suppose that thinking can
be guided in a variety of ways. Our thoughts can be guided back to goal-relevant
information, as happens when we are goal-directed, or guided back to affectively salient
information, as happens when we ruminate. Although different neurocognitive
processes may underlie these two kinds of thinking, we argue that both kinds
implement guidance in our technical sense.
Consider goal-directed thinking. In goal-directed thinking, one would feel pulled
back to pursuing the goal were one to focus on information that seems irrelevant to it.
Imagine a mathematician intently constructing a proof in a busy library. Her
attentiveness manifests partly in how her attention is guided back from distractors.
Were she to become momentarily distracted by students shuffling their papers, she
would likely feel frustrated and pulled back to her work. Thus her mental activity is
guided in its being regulated in relation to her goal.
We hypothesize that rumination also is guided. We predict that individuals who
break away from their ruminative thoughts will feel pulled or drawn back to them. For
thinking to be pulled or drawn back to a particular focus in this way is precisely for it to
be counterfactually regulated and thus guided.
Our hypothesis that rumination is guided does not entail that it has the same
psychological and neural profile as goal-directed attention (Table 1). On the contrary, as
mentioned above, the genus “guided thought” allows for there being different species
of guided thinking that are subserved by different brain processes. For example, topdown cognitive control processes appear to be largely responsible for the guidance of
goal-directed thought (e.g. Corbetta & Shulman, 2002; Kane & Engle, 2002), whereas
affective biases of attention and memory (Todd, Cunningham, Anderson, & Thompson,
2012) likely play a strong role in one’s being guided toward ruminative thoughts.
Furthermore, goal-directed attention is paradigmatically voluntary, whereas rumination
typically is involuntary. The ruminator might complain, “I don’t want to think about
10
distressing thoughts; they just keep pulling me back in.” Nevertheless, we propose that
rumination and goal-directed attention are both guided in our technical sense: in either
case, if individuals were mentally distracted from their current focus, they would feel
their thoughts pulled back to it.
That goal-directed thought and rumination are both guided explains why both
kinds of thinking are dynamically stable. Our thoughts remain fixed on a restricted set of
information because they are guided to remain there.
In contrast, we define mind-wandering as unguided thinking (Irving, 2015).
Whereas a guided thinker would feel pulled back if she were distracted from her current
focus, an unguided thinker wanders from one topic (dinner) to another (computer
code); her mind drifts unchecked, with nothing to pull her back to a particular focus.
This lack of guidance explains why mind-wandering has an itinerant or unstable
dynamics rather than a stable dynamics. Thoughts drift from topic to topic because
nothing holds them in place. Thus our definition captures the dynamics of mindwandering. Moreover, we provide a principled way to distinguish between different
varieties of task-unrelated and stimulus-independent thought: in rumination, thoughts
are guided to remain on the same topic and hence exhibit greater dynamical stability,
whereas in mind-wandering, thoughts are unguided and hence exhibit greater
dynamical instability.
Our account avoids the earlier mentioned dilemma arising from the possibility
of task-related mind-wandering. Recall that both wandering thoughts and goal-directed
thoughts can be related to everyday tasks, such as planning dinner or writing computer
code. Because of this possibility, current definitions of mind-wandering cannot properly
distinguish it from goal-directed thinking. According to our account, the difference
between them concerns how trains of thought are guided as they unfold over time.
Goal-directed thinking is guided to remain on the same topic (e.g., writing code). Mindwandering is unguided, so it is free to drift from one topic to the next. Its dynamics are
unguided even when one’s mind wanders to a personal goal (such as writing computer
11
code). The crucial point is that if one’s thoughts were to drift onward (e.g., to a joke one
head today), one would not be drawn back to a particular focus.
Our definition of mind-wandering as unguided thinking overcomes the
limitations of previous definitions in the empirical literature. Our definition is based on
an account wherein stretches of mind-wandering consist of trains of thought whose
dynamics are unguided. This account, however, is not the only account of mindwandering in the philosophical literature. We will now review two other accounts and
critically assess them in relation to our own.
4 Mind-Wandering as Thought Lacking “Veto Control”1
Thomas Metzinger (2013) proposes a theory of mind-wandering that helps to explain
the relationship between mind-wandering and cases of goal-directed thinking, such as a
mathematician constructing a proof. Metzinger allows that mind-wandering can be goaldirected, and so his theory can accommodate the evidence that our minds frequently
wander to our personal goals. Nevertheless, he maintains that mind-wandering differs
from fully “autonomous” forms of goal-directed thinking, such as a mathematician
consciously constructing a proof. In Metzinger’s view, goal-directed thinking is “mentally
autonomous” only if one has the kind of cognitive control over one’s thoughts that he
calls “veto control.”
The concept of “veto control” comes from cognitive science. It refers to the
person’s ability to “withhold a… [behaviour]2 whose preparation and path towards
execution has already begun” (Filevich, Kühn, & Haggard, 2012, p. 1108). Consider the
following example where you exercise veto control:
You are posting a letter, and are just about to release your grip on it and let
it fall into the post box, when you suddenly get the feeling that you should
check whether you put a stamp on the envelope. You tighten your grip and
inspect the letter (Filevich et al., 2012, p. 1108).
12
Note that you would have possessed veto control even if you had released the letter,
because veto control requires only that you are able––and know that you are able––to
suspend the relevant behaviour (Metzinger, 2013, p. 4).
Metzinger argues that when our minds wander, we lack veto control over our
thoughts. Thus he distinguishes mind-wandering from autonomous goal-directed
thinking that we can suspend at will—for example, consciously constructing a math
proof. In support of this view, Metzinger appeals to evidence that mind-wandering
unfolds without meta-awareness (Schooler et al., 2011).3 “Meta-awareness” is defined
as one’s explicit knowledge of the current contents of thought or one’s current
conscious state (Schooler, Smallwood, Christoff, Handy, Reichle, & Sayette, M. A., 2011).
Thus meta-aware mental states are higher-order mental states that are about one’s
ongoing or just past mental states. One example is a lucid dreamer’s meta-awareness
that she is dreaming. Another example is the sudden realization that your mind was
wandering.
Metzinger's argument has two premises. First, meta-awareness is necessary for
veto control over a mental state or process (Metzinger, 2013, p. 3): a person cannot
knowingly terminate something of which she is unaware. (Suppose I discover that you
were not paying attention and I ask, “Why didn’t you stop your mind from wandering
earlier?” You might reasonably respond, “I didn’t know my mind was wandering until
just now.”) Second, Metzinger contends that whenever a person’s mind is wandering,
she lacks meta-awareness of her wandering thoughts. From these two premises, it
follows that people lack veto control over their wandering thoughts. Thus, Metzinger’s
account suggests that mind-wandering be defined as thinking lacking meta-awareness
and veto control.
The problem with this account is that the second premise—that mindwandering always occurs without meta-awareness—is questionable. The evidence
suggests that although mind-wandering sometimes occurs without meta-awareness, it
does not always do so (Smallwood & Schooler, 2006; Schooler, Smallwood, Christoff,
Handy, Reichle, & Sayette, M. A., 2011). Many studies of mind-wandering use self-
13
reports to assess meta-awareness. Individuals who catch themselves mind-wandering or
who report that their minds were wandering upon being probed are asked whether they
were previously aware of their mind-wandering. For example, Smallwood and
colleagues gave participants the following instructions in order to distinguish between
aware (“tuning out”) versus unaware (“zoning out”) mind-wandering:
Tuning Out: Sometimes when your mind wanders, you are aware that your
mind has drifted, but for whatever reason you still continue to read. This is
what we refer to as “tuning out”––i.e., when your mind wanders and you
know it all along.
Zoning Out: Other times when your mind wanders, you don’t realize that
your thoughts have drifted away from the text until you catch yourself. This
is what we refer to as “zoning out”––i.e., when your mind wanders, but you
don’t realize this until you catch it (Smallwood, McSpadden, & Schooler,
2007, p. 533).
Across all conditions, Smallwood and colleagues found that tuning out occurred as
frequently or more frequently than zoning out. Therefore, it may be that mindwandering occurs at least as often with meta-awareness as without it (cf. Smallwood et
al., 2004; Smallwood, Beach, Schooler, & Handy, 2008).
Metzinger argues that cases of apparently autonomous mind-wandering
involve the mere “illusion of control” (Metzinger 2013; cf. Schooler et al. 2011), so he
might question the reliability of reports of “tuning out” (mind-wandering with
awareness). Nevertheless, tuning out and zoning out have different behavioural and
neural profiles (Schooler et al. 2011). For example, compared to tuning out, zoning out
is associated with better reading comprehension (Smallwood et al. 2008) and more
activation of default-mode network regions and executive-function regions (Christoff et
14
al. 2009) that are generally associated with mind-wandering (Fox et al. 2015). It is not
clear how to explain these differences, if reports of tuning out are entirely illusory.
Another limitation of Metzinger’s theory is that it neglects the dynamics of
mind-wandering. Veto control and the presence versus absence of meta-awareness
have no essential connection to how one’s thoughts unfold over time, according to his
account. Therefore, his account cannot distinguish mind-wandering from rumination.
Ruminators often seem to lack meta-awareness and hence veto control over their
thoughts. For example, a commuter might fixate on her problems and distress without
realizing that she has stopped watching for her subway stop. Because she is unaware
that she has begun to ruminate, she cannot disengage from (veto) her distress and bring
herself back on task. Indeed, trait ruminators show impaired disengagement across a
range of tasks (Whitmer & Gotlib, 2013). This finding suggests that rumination
frequently unfolds without veto control. Metzinger’s theory does not have the
resources to explain how mind-wandering differs from this antithetical phenomenon of
rumination.
Our account of mind-wandering as unguided thinking has two advantages over
Metzinger’s account (Irving, 2015, pp. 567–568). First, we allow that mind-wandering
can unfold without meta-awareness. During cases of tuning out—“when your mind
wanders and you know it all along” (Smallwood et al., 2007, p. 533)––we propose that
you have meta-awareness of and thus veto control over your stream of unguided
thoughts. Second, our account captures the dynamics of mind-wandering. Accordingly,
we can explain how rumination and mind-wandering differ: whereas the former is
guided, the latter is not.
5 Mind-Wandering as Disunified Thinking
Peter Carruthers (2015) and Fabian Dorsch (2014) independently have proposed
accounts of mind-wandering that rival the explanatory power of our own account. We
focus on Carruthers’s theory but our critical discussion applies to both philosophers.
Carruthers discusses mind-wandering because it provides an apparent counterexample
15
to his view that all thinking is active and goal-directed. He concedes that mindwandering does “not seem, introspectively, to be active in nature. Sometimes one’s
thoughts change direction for no apparent reason (especially when one’s mind is
wandering)” (Carruthers, 2015, p. 166). Therefore, he must explain away the apparent
difference between mind-wandering and goal-directed thought.
Carruthers explains away this apparent difference by drawing an analogy
between mind-wandering and wandering around a garden: “Mind wandering is active, I
suggest, in much the same sense that someone physically wandering around in a garden
is active” (Carruthers, 2015, pp. 167–168). Dorsch (2014) draws a similar analogy
between mind-wandering and physically wandering around a city. Both philosophers
maintain that short stretches of physical and mental wandering are active. As you
wander around a garden you might actively smell a rose or wish upon a dandelion.
Similarly, you might actively plan dinner or write code while your mind wanders.
Nevertheless, longer stretches of physical and mental wandering seem passive because
no overarching goal unifies your thoughts. Given this point, Carruthers and Dorsch can
explain away the apparent difference between mind-wandering and paradigm cases of
goal-directed thought, such as a mathematician solving a proof in her head. Whereas
the mathematician’s thoughts are all unified under a single goal (solving the proof), the
mind-wanderer’s thoughts concern many goals (planning dinner, writing code, and so
on). Thus mind-wandering seems more passive than goal-directed thought, though both
are active when we look at them closely enough.
Carruthers’s and Dorsch’s discussions suggest that mind-wandering be defined
as disunified thinking. A sequence of thoughts constitutes mind-wandering if and only if
those thoughts are not unified under a common goal. This definition has major
advantages. First, it captures the dynamics of mind-wandering: by definition, our
wandering thoughts are dynamically unstable in the sense that they are not unified
under a common goal. Second, this definition can account for the puzzling relationship
between mind-wandering and goal-directed thought. On the one hand, short stretches
of mind-wandering are related to tasks (such as preparing for a quiz), as the empirical
16
evidence suggests. On the other hand, mind-wandering contrasts with goal-directed
thinking because it is disunified.
Despite the advantages of this conception of mind-wandering, it has a
problematic consequence, which we can bring out in the following example. Imagine
someone who works for ten minutes composing part of a lecture, then opens his web
browser and responds to some emails for six minutes, and then looks outside the
window, studying the pigeons across the street, for ninety seconds. Furthermore,
suppose that the person attentively pursues each goal. Nevertheless, no overarching
goal unifies this whole sequence of thoughts, so they count as mind-wandering. Shifting
from goal to goal in this way seems commonplace. Therefore, if we define mindwandering as disunified thinking, most trains of goal-directed thinking will count as
mind-wandering. But then it seems that Carruthers and Dorsch have not captured the
difference between mind-wandering and goal-directed thinking at all.
A deeper problem lurks in the vicinity. Whether thinking counts as disunified,
and thus as mind-wandering, depends on the scale of observation or how far we zoom
out (Figure 1). Suppose we examine the person’s thoughts in the previous example. In
the first five minutes, his attention is wholly guided by the goal of composing the
lecture. During that interval, his attention is unified and his mind is not wandering. But if
we zoom out to a seventeen-minute interval, we find thoughts about three separate
goals—composing a lecture, writing emails, and watching pigeons. From this broader
perspective, his attention is disunified and his mind is wandering. The problem is that
we lack principled reasons for deciding how far to zoom out, and therefore we lack
principled reasons for saying whether his mind is wandering at any given point in time.
This consequence undermines the scientific methods we use to study mindwandering. These methods require that we be able to specify when the mind is
wandering versus when it is not, so that we can study the distinctive features of
wandering thoughts (such as their contents and their neural correlates) versus other
kinds of thoughts. For example, Christoff et al. (2009) compared neural activation when
individuals were concentrating on a task versus mentally wandering away from it. If we
17
define mind-wandering as disunified thinking, then we cannot use these methods,
because if we zoom out, then the on-task thoughts are probably going to count as
wandering thoughts. No methodological innovation could solve this problem. In other
words, given the definition of mind-wandering as disunified thinking, there will be no
principled way to distinguish mind-wandering from goal-directed thought. Therefore,
this definition is a non-starter for the cognitive science of mind-wandering.
In contrast, our definition of mind-wandering as unguided thought does not
face these problems. We provide an easy way to distinguish goal-directed and
wandering thought: the former is guided; the latter is not. Therefore, our definition is
preferable on conceptual grounds as well as being more amenable to empirical
investigation.
6 Conclusion
Psychologists, cognitive neuroscientists, and philosophers should be partners in the
scientific investigation of mind-wandering. The challenges facing our young field are not
only empirical but also conceptual and theoretical. Our chapter begins with a
philosophical critique of the most widely accepted definitions of mind-wandering in
cognitive psychology. This critique stems from the idea that mind-wandering is
fundamentally dynamic. Our definition uses the technical philosophical notion of
“guidance” to capture its dynamics. Compared to the other extant philosophical
definitions, our definition of mind-wandering as unguided thought is not only more
theoretically defensible but also more scientifically tractable. Putting this definition to
work in cognitive science will require close collaborations with psychologists and
cognitive neuroscientists. For example, difficult questions remain about how to measure
the dynamics of mind-wandering (Christoff, 2012) and how to relate the philosophical
notion of guidance to dynamical neural networks and psychological processes (Christoff,
Irving, Fox, Spreng, & Andrews-Hanna, 2016). The path forward requires that
psychologists, cognitive neuroscientists, and philosophers work together to advance our
understanding of mind-wandering.
18
Notes
1
Much of the material for this section is adapted from Irving (2015).
2
Filevich and colleagues originally defined “veto control” as the ability to “withhold an
action.” We have changed the definition, replacing action” with “behaviour,” because
veto control arguably is necessary for action (as opposed to mere movement). In that
case, defining “veto control” as the ability to withhold an action would trivially imply
that one never lacks veto control.
3
Thus Metzinger expands upon Smallwood and Schooler’s (2006) thesis that mind-
wandering differs from goal-directed thought because the former always begins without
meta-awareness.
19
Table 1: Varieties of Guided Thinking
Goal-directed thinking
Rumination
Guided towards
Goal-relevant information
Distress, etc.
Implemented Thought
Cognitive control
Affective biases
Voluntary
Yes
Often not
Guided
Yes
Yes
Dynamically Stable
Yes
Yes
20
Figure 1: Disunity and Zoom
21
References
Baird, B., Smallwood, J., & Schooler, J. W. (2011). Back to the future: Autobiographical
planning and the functionality of mind-wandering. Consciousness and Cognition,
20(4), 1604–1611. http://doi.org/10.1016/j.concog.2011.08.007
Brownstein, M., & Madva, A. (2012). The normativity of automaticity. Mind & Language,
27(4), 410–434.
Callard, F., Smallwood, J., Golchert, J., & Margulies, D. S. (2013). The era of the
wandering mind? Twenty-first century research on self-generated mental activity.
Frontiers in Psychology, 4(Article 891).
Carruthers, P. (2015). The centered mind: what the science of working memory shows us
about the nature of human thought. Oxford University Press.
Christoff, K. (2012). Undirected thought: Neural determinants and correlates. Brain
Research, 1428, 51–59.
Christoff, K., Gordon, A. M., Smallwood, J., Smith, R., & Schooler, J. W. (2009).
Experience sampling during fMRI reveals default network and executive system
contributions to mind wandering. Proceedings of the National Academy of Sciences,
106(21), 8719–8724.
Christoff, K., Irving, Z. C., Fox, K. C. R., Spreng, R. N., & Andrews-Hanna, J. R. (2016).
Mind-wandering as spontaneous thought: A dynamic framework. Nature Reviews
Neuroscience.
Corbetta, M., & Shulman, G. L. (2002). Control of goal-directed and stimulus-driven
attention in the brain. Nature Reviews Neuroscience, 3(3), 201–15.
http://doi.org/10.1038/nrn755
Dorsch, F. (2014). Focused Daydreaming and Mind-Wandering. Review of Philosophy
and Psychology., Advance on.
Filevich, E., Kühn, S., & Haggard, P. (2012). Intentional inhibition in human action: The
power of no. Neuroscience & Biobehavioral Reviews, 36(4), 1107–1118.
Fox, K. C. R., Spreng, R. N., Ellamil, M., Andrews-Hanna, J. R., & Christoff, K. (2015) The
wandering brain: Meta-analysis of functional neuroimaging studies of mind-
22
wandering and related spontaneous thought processes. Neuroimage 111(1): 611621.
Frankfurt, H. (1978). The problem of action. American Philosophical Quarterly, 15(2),
157–162.
Hobbes, T. (1651). Leviathan, or the matter, forme and power of a commonwealth
ecclesiasticall and civil. New Haven: Yale University Press.
Irving, Z. C. (2015). Mind-wandering is unguided attention: Accounting for the
``purposeful’' wanderer. Philosophical Studies.
Kane, M. J., Brown, L. H., McVay, J. C., Silvia, P. J., Myin-Germeys, I., & and Thomas R.
Kwapil. (2007). For whom the mind wanders, and when: An experience-sampling
study of working memory and executive control in daily life. Psychological Science,
18(7), 614–621.
Kane, M. J., & Engle, R. W. (2002). The role of prefrontal cortex in working-memory
capacity, executive attention, and general fluid intelligence: an individualdifferences perspective. Psychonomic Bulletin & Review, 9(4), 637–671.
http://doi.org/10.3758/BF03196323
Killingsworth, M. a, & Gilbert, D. T. (2010). A wandering mind is an unhappy mind.
Science (New York, N.Y.), 330(6006), 932. http://doi.org/10.1126/science.1192439
Klinger, E. (1999). Thought flow: Properties and mechanisms underlying shifts in
content. In J. A. Singer and P. Salovey (eds.), At Play in the Fields of Consciousness:
Essays in Honor of Jerome L. Singer (pp. 29-50). Mahwah, NJ, US: Lawrence Erlbaum
Associates Publishers.
Metzinger, T. (2013). The myth of cognitive agency. Frontiers in Psychology, 4(Article
931).
Metzinger, T. (2015). M-Autonomy. Journal of Consciousness Studies, 22(11-12), 270–
302.
Morsella, E., Ben-Zeev, A., Lanska, M., & Bargh, J. a. (2010). The Spontaneous Thoughts
of the Night: How Future Tasks Breed Intrusive Cognitions. Social Cognition, 28(5),
641–650. http://doi.org/10.1521/soco.2010.28.5.641
23
Nolen-Hoeksema, S., Wisco, B. E., & Lyubomirsky, S. (2008). Rethinking rumination.
Perspectives on Psychological Science, 3, 400–424.
Pacherie, E. (2008). The phenomenology of action: A conceptual framework. Cognition,
107(1), 179–217. http://doi.org/10.1016/j.cognition.2007.09.003
Railton, P. (2006). Normative guidance. Oxford Studies in Metaethics, 1, 3–34.
Schooler, J. W., Smallwood, J., Christoff, K., Handy, T. C., Reichle, E. D., & Sayette, M. A.
(2011). Meta-awareness, perceptual decoupling and the wandering mind. Trends in
Cognitive Sciences, 15(7), 319–326. http://doi.org/10.1016/j.tics.2011.05.006
Smallwood, J., Beach, E., Schooler, J. W., & Handy, T. C. (2008). Going AWOL in the
brain: Mind wandering reduces cortical analysis of external events. Journal of
Cognitive Neuroscience, 20(3), 458–469.
Smallwood, J., Davies, J. B., Heim, D., Finnigan, F., Sudberry, M., O’Connor, R., &
Obonsawin, M. (2004). Subjective experience and the attentional lapse: Task
engagement and disengagement during sustained attention. Consciousness and
Cognition, 13(4), 657–690.
Smallwood, J., McSpadden, M., & Schooler, J. W. (2007). The lights are on but no one’s
home: meta-awareness and the decoupling of attention when the mind wanders.
Psychonomic Bulletin & Review, 14(3), 527–533.
http://doi.org/10.3758/BF03194102
Smallwood, J., & Schooler, J. W. (2006). The restless mind. Psychological Bulletin, 132(6),
946–958.
Smallwood, J., & Schooler, J. W. (2015). The science of mind wandering: empirically
navigating the stream of consciousness. Annual Review of Psychology, 66, 487–518.
Sutton, J. (2010). Carelessness and inattention: Mind-wandering and the physiology of
fantasy from Locke to Hume. In C. T. Wolfe & O. Gal (Eds.), The Body as Object and
Instrument of Knowledge (pp. 243–263). New York: Springer.
Thompson, E. (2015). Waking, Dreaming, Being: New Light on the Self and
Consciousness from Neuroscience, Meditation, and Philosophy. New York: Columbia
University Press.
24
Todd, R. M., Cunningham, W. A., Anderson, A. K., & Thompson, E. (2012). Affect-biased
attention as emotion regulation. Trends in Cognitive Sciences, 16(7), 365–372.
Whitmer, A. J., & Gotlib, I. H. (2013). An attentional scope model of rumination.
Psychological Bulletin, 139(5), 1036–61. http://doi.org/10.1037/a0030923
Zetsche, U., & Joormann, J. (2011). Components of interference control predict
depressive symptoms and rumination cross-sectionally and at six months followup. Journal of Behavior Therapy and Experimental Psychiatry, 42(1), 65–73.
http://doi.org/10.1016/j.jbtep.2010.06.001